1. Field of the Invention
The present invention relates to a portable communications apparatus, such as a cellular phone, a PDA (Personal Digital Assistant) an HHP (Hand-Holding Phone), etc., and more particularly to a key input device for a portable communication apparatus that includes a main body housing and a sliding body housing mounted on the main body to be slid thereon, and a sliding module therefor.
2. Description of the Related Art
Portable communications apparatuses are commonly represented by a mobile communications terminal providing people with wireless communication services of various content, such as voice communication, short message exchange, mobile banking, TV (Television) broadcasting, on-line games, video on demand, etc.
Mobile communications terminals are generally classified according to their external forms into a bar-type with a single housing containing a communications circuit and input and output devices, such as a transmitting part and a receiving part, a flip-type with a flip cover attached to a bar-type, and a folder-type with input and output devices respectively arranged in a pair of housings capable of being folded or spread to or from each other. In addition, a sliding-type terminal has been recently introduced in order to meet various desires and needs of the user together with enhanced convenience.
Mobile communications services have been developed to provide multimedia services enabling transmission of game, music and video files, and on-line games in addition to original voice communication and short message exchange. Such varieties of mobile communications contents have caused design development of mobile communications terminals to enhance input/output devices for meeting them. However, limitations of allowable mounting space in a mobile communications terminal makes it difficult to extend the input/output devices beyond their original basic functions. For example, a sliding-type mobile communications terminal presently available in the market is designed to enable the sliding body housing to be slid along a single direction relative to the main body housing by about half the length of the main body housing, thus restricting spaces for mounting input keys and an LCD (Liquid Crystal Display) therein.